1. Field of the Invention
The present invention relates to a coupling structure of a threaded member and a synthetic resin part for a vehicle used for integrally incorporating a threaded member such as a bolt or a nut into a part or component of synthetic resin mounted on a vehicle.
2. Description of the Related Art
It is a conventional practice that such a threaded member is partially or entirely integrally embedded in a part of synthetic resin simultaneously with the formation of the part by injection molding or the like (for example, see Japanese Utility Model Application Laid-open Nos. 62-484 and 61-67080).
In the conventional structure, however, it is required that the threaded member be positioned and retained at a predetermined location within a mold in the course of molding the part. Since this operation is not easy, the operating efficiency is poor, and this is disadvantageous for saving the operating labor.
In the conventional structure, the threaded member made of metal is non-separatably integrally fixed in the part made of synthetic resin after the formation of the part by molding, resulting in a problem that a defectively molded part or a part which has been put into service, cannot be recycled as it is.
The present invention has been accomplished in view of the above-mentioned circumstances, and it is an object of the present invention to provide a coupling structure of a threaded member and a synthetic resin part for a vehicle, wherein the problem associated with the convention structure can be solved.
To achieve the above object, according to a first aspect and feature of the present invention, there is provided a coupling structure of a threaded member and a synthetic resin part for a vehicle comprising a part of synthetic resin and mounted on a vehicle, and a threaded member detachably mounted in the part, the part being provided with a retaining portion for retaining at least a portion of the threaded member against rotation relative to each other, and a claw means capable of disengageably engaging with the threaded member so as to inhibit the separation of the threaded member from the retaining portion. With such feature, after formation of the part of synthetic resin by molding, the threaded member can be fixed easily in a post-mounting manner in the part only by retaining at least a portion of the threaded member in the retaining portion of the part against rotation relative to each other and locking the threaded member on the claw means of the part after formation of the part of the synthetic resin. Even after the fixing of the threaded member, if the threaded member is separated from the claw means and drawn from the retaining portion, the threaded member can be separated easily from the part. Therefore, it is unnecessary to specially position and retain the threaded member in a mold in the course of molding the part, leading to a correspondingly simplified forming step. This contributes to an enhancement in forming operation efficiency and the saving of the operating labor. The part, which has been defectively molded or has been put into service, can be recycled as it is, by simply removing the threaded member therefrom. This is advantageous for the resource-saving for the part of synthetic resin for the vehicle.
According to a second aspect and feature of the present invention, in addition to the first feature, the claw means is provided to protrude on a back of the part of synthetic resin, and another threaded member is screwed to the threaded member from a surface side of the part. With such feature, the claw means protrudes on the back of the part of synthetic resin and is hidden from the surface of the part keeping a good external appearance. Moreover, the claw means cannot protrude on a screwing seat surface located on the surface of the part. Therefore, there is no possibility that the claw means may be a hindrance to a screwing operation. In addition, even if a large thrust load directed to the surface of the part is applied to the threaded member with the screwing of the threaded member, this thrust load need not be received by the claw means and hence, the claw means has an improved durability.
According to a third aspect and feature, in addition to the first or second feature, the part of synthetic resin is a seat bottom plate mounted on a saddle-riding vehicle, and the threaded member is used to detachably secure the seat bottom plate to a vehicle body. With such feature, it is possible to provide an enhancement in efficiency of and a labor-saving of the operation of forming the seat bottom plate having the threaded member mounted therein, and moreover, it is possible to promote the recycling of the seat bottom plate.
The above and other objects, features and advantages of the invention will become apparent from the following description of the preferred embodiment taken in conjunction with the accompanying drawings.